Corrosion behavior of AISI302 steel treated by elevated temperature nitrogen plasma immersion ion implantation

The corrosion behavior of AISI302 steel implanted with nitrogen at elevated temperature was investigated by electrochemical impedance spectroscopy. Equivalent circuits for explaining the impedance characteristics are proposed. The thick passive layer containing Cr2O3 and the expanded austenite layer in the sub-surface worked together, resulting in the high corrosion resistance.